The invention relates to a distillation plant with a column and a heat pump that operates between a sump vaporizer and an exhaust vapor compressor. The use of the plant is described.
In a distillation column heat is supplied to a sump for the production of a vapor, whereas in a column head a corresponding amount of heat is conveyed off for the liquefaction of vapors (often called exhaust vapors). The supply of heat in the sump and the conveying off of heat in the head are advantageously coupled via a heat pump process by means of which a heat transport as well as a heat conversion (i.e. temperature increase of the transported heat) can be carried out. A preferred method, the xe2x80x9cdirect exhaust vapor compressionxe2x80x9d, can in many products not be used due to polymerization, decomposition, corrosion, low vapor density, etc. In such cases one distills conventionally without heat pumps or with a heat pump of which the working medium is a separate material which is conducted in an auxiliary circulation. In this the heat supply and the conveyance off of heat are carried out via indirect heat exchange in a sump vaporizer and in an exhaust vapor condensator respectively. Various materials come under consideration as working medium of the heat pump. For thermodynamic reasons and thanks to its lack of hazard to the environment, water is more advantageous in comparison with other possible materials and is therefore to be preferred.
A disadvantage of the use of heat pumps is that heat pump compressor failure results in a long standstill time in practice since the compression must be done with machines for which as a rule no rapid replacement is available.
The object of the invention is thus to provide a distillation plant in which this disadvantage with respect to a compressor failure is eliminated by means of suitable measures. This object is satisfied by a plant having a heat source (6) and a heat sink (7) which can be substituted for the heat pump.
The distillation plant comprises a column and a heat pump that operates between the sump vaporizer and an exhaust vapor condensator. The heat pump is substitutable by devices which can be switched to the sump vaporizer and the exhaust vapor condensator when required. These substituting devices comprise devices for the production of vapor or the provision of a coolant respectively as well as connection means. The coolants can be liquids (water) or gases (air).
A method of use, of such a plant is also set forth.